Double-casing pump



.Jan. 10, 19 28.

A. HOLLANDER DOUBLE CASING PUMP Filed June 2, 1926 fnven t, or.

a/zu' 440W V H a rney.

into a Patented Jan. 10, 1928.

UNITED STATES PATENT OFFICE.

ALAIDAR HOLLANDER, OI? BERKELEY, CALIFORNIA, ASSIGNOR TO BYRON JACKSON PUMP MFG. 60., OF BERKELEY, CALIFORNIA, A CORPORATION OF CALIFORNIA.

, DOUBLE-CASING your.

Application filed J'une 2, 1926. Serial No. 113,172.

.lers mounted to operate synchronously as upon the same shaft, and each of the said casings being enclosed and spaced from a housing, whereby fluid pressure which is introduced between the casings and their respective housings, acts to compress the easings. This compressive force is in each instance in excess of the maximum internal pressure tending to ex and the casings, with the result that the di erential pressure acting upon the casing is a compressive force during all times when the pump is in operation.

These objects I accomplish by introducing the discharge pressure from the highest impeller stage in each casing between the said casing and its corresponding housings, as set Cgenerally forth in my above recited co-pen mg application, and in my present invention, in addition thereto, I divide the impellers and therefore the pump stages' plurality of groups each of sai groups eing provlded with its external ousmg and these groups in turn are connected in series, so that the housing of the groups of the higher stages only is ex osed to maximum bursting pressure an the housings enclosing the casings of lowerstage to a reduced bursting pressure, and at the same time maintaining a lower differ ential pressure upon each of the groups of casings. 5

Moreover the discharge pressure from each group is employed as a compressive force acting externally of the casing of the group and is as high as or higher tian any of the internal pressures within the respective casing or casings.

By referring toithe accompanying drawing my inventlon will be made clear.

Fig. 1 is a longitudinal cross section of a pump employing my invention.

Fig, 2 is a cross section of. Fig. 1 on the line II II thereof.

Throughout the figures similar numerals refer to identical parts.

A suction supply inlet is shown by the numeral 1, by which fluid is introduced as indicated by the arrow 2, into the suction 3 and thereafter is acted upon by a series of impellers which in the drawing here shown, correspond with six stages of pressure increase.

These six impellers forming the first group, are enclosed within the casing 4 as set forth in my above recited co-pending application, and are similar in all respects to the impellers 9 to 13 enclosed in thecasing 14 shown in section on the right hand of Figure 1, and the discharge at the highest pressure from'this group is in the direction of the arrow 5 and through the channel way 6 and thence passes as indicated by the ar fows'i, into the suction inlet of the impel- Other impellers 9, 10, 11, 12 and 13, are mounted in series forming six additional stages of pressure increase within the secon casing 14 from which fluid pressure from the highest stage, namely runner13 is delivered in the direct-ion of the arrow 15 through the op'lening 16, and also establishes a pressure in t espace 45 between the casing 18 and the housing 14.

The impellers are all balanced against each other.

Enclosing the casing 4 is the primary housin 17 and enclosing the second casing 14 is t 1e secondary housing 18.

The housings 17 and 18 are separated by the rin or diaphragm member 20 and ms ing end 19 and'the housings are spaced from their respective casings by the spaces 45 and 46 respectively so that the casing 4 is "subjected at all times when the pump is operating to the external compressive force in the channel 6 and space 46 which corresponds with the pressure established by the highest stage of the grou of impellers in casing 4., less the interna pressure within the casing 4 in its several stages.

The result will be a differential compressive force acting about the entire outer surface of the casing 4, thus enabling the thick ness of metal in the said intricate casting to be reduced to a minimum;

In like manner the casing 14 is subjected to an external pressure corresponding with the suction inlet pressure at 1 is zero,

sembly of my the delivery pressure from the runner 13, reduced by t e inlet pressure which will never be substantially less than that of the pressure in channel 6 as established by the first group of impellers.

An elastic packing is preferably employed at 40.

To take a numerical example we will suppose that each impeller corresponds with one hundred pounds pressure and assuming thfit t e pressure discharge at 16 will therefore be 1200 pounds, there being in the pump here illustrated, 2 groups of 6 impellers each acting in series, and therefore each successive impeller stage raises the pressure 100 pounds per square inch.

The pressure in the channel 6 will be that established by the first six impellers, or 600 pounds and there will therefore be 600 pounds per square inch exerted about the entire exposed surface of the casing 4 holding the halves of the casing together and tending to force the casing against seat 30 and maintaining at all times a tight joint therewith.

There will be between casing 14 and housing 18, the difference between 1200 pounds at 16, and 600 pounds at 6, or 600 pounds tending to retain the casing 14 with its halves pressed together under great pressure and against the diaphragm 20 with an equivalent pressure.

All parts of the first group of six stages may therefore be duplicated in the second group, whereas the housing 18, a casting of extremely simple design and construction only, will be subjected to the 1200 pound or maximum pressure and the primary housing 17 will be subjected to only 600 pounds bursting pressure.

Attention is directed to the absence of bolts to hold the parts to ether in an axial direction, the external collapsing pressures about the casings beingdepended upon for this purpose.

The housing 17 it is to be noted, is closed on its left hand end by the head 32 carrying a conventional bearing and gland at 33 and on its right hand end by the diaphragm 20, casing end 19 and flange 34 of the housing 18.

Particular attention is directed to the aspressure joint to be packed, to-wit, between the flanges 34 and 36.

To assemble the parts the casing ofthe higher stage is introduced into the housing 18, its end telescoping into the end 35 of the said housing and against the elastic packing 40.

The ring 20 is then introduced and the housing 17 then slipped over the casing 4 to a contact at the joint 30.

pump, there being but one The flanges 34 and 36 are then bolted together witi conventional packing therebetween, and the pump is assembled and ready for operation.

As shown in casings 4 and 14 on a plane through the shaft axis thus making but a single joint which is held together as by the bolts 41, 42, 43, 44. lVhen the pump is operating, there is no tension stress on these bolts because of the external pressures in the spaces 6 and 45, which being in excess of any of the internal pressures result in the partsof the casings 4 and 14 being retained under compressive strains.

The elastic member at 40 allows of any expansion or contraction between the casings and the housings as due to temperature and pressure variations while retaining the parts in assembled relation during assembly and when the pump is not operating and is free from internal fluid pressures.

I claim:

1. In a fluid pressure pump, a main shaft, a plurality of groups of impellers mounted on said shaft each of said groups enclosed in ascasing, each of said casings having a suction inlet and a discharge port, a housing enclosing each of said casings with a space between each casing and housing, an inlet in one housing for suction fluid to one group of impellers and an outlet from another housing for pumped fluid from another group of impellers, sealing means between the respective housings and suction inlets of the casings separating the respective spaces, a discharge passage from each of said casings communicating with the corresponding space whereby the discharged fluid pressure of each group of impellers is established in the space between its casing and associated housing.

2. In a fluid pressure pump a main shaft a plurality of groups of impellers mounted on said shaft each of said groups enclosed in a casing, each of said casings having a suction inlet and a discharge port, a housing enclosing each of said casings with a space between each casing and housing, an inlet in one housing for suction fluid to one group of impellers and an outlet from another housing for pumped fluid from another group of impellers, sealing means between the respective housings and suction inlets of the casings separating the res ective spaces, a discharge passage from eac of said casings communicating with the corresponding space whereby the discharged fluid ressure of each group of impellers is established in the space between its casing and associated housing and said sealing means including a flanged joint between each casing and housing.

3. In a fluid pressure pump a main shaft, a plurality of groups of impellers mounted on said shaft each of said groups enclosed in Fig. 2, I prefer to split the of impellers and an outlet from another housing for pumped fluid from another group of impellers, sealing means between the respective housings and suction inlets of the casings separating the respective spaces, a discharge passage from each of said casings communicating with the corresponding space whereby the discharged fluid pressure of each group of impellers is established in the space between its casing and associated housing, and said sealing means including diaphragms interposed between the said housings and providing seats against which the respective casings are supported.

4. In a fluid pressure pump a main shaft, a plurality of groups 0t impellers mounted on said shaft each of said groups enclosed in a casing, each of said casings having a suction inlet and a discharge port, a housing enclosing each of said casings with a space between each casing and housing, an inlet in one housing for suction fluid to one group of impellers and an outlet from another housing for pumped fluid from another group of impellers, sealing means between the respective housings and suction inlets ot' the casings separating the respective spaces, a discharge passage from each of said casings communicatin with the corresponding space whereby t e discharged fluid pressure of eachgroup of impellers is establisliedin the space betweemits casing and associated housing, and said sealing means including diaphragms interposed between the said housings" and providing seats against which the respective casings are supported, and bearings for said shaft supported by said housings.

ALADAR HOLLANDER. 

